The pedal car is designed to bridge the gap between cars and bikes culminating in a holistically sustainable passenger vehicle.

In need of a client to fulfill the Graduate Diploma requirements, I approached Simon at Port Adelaide Enfield City Council. After some discussions, we decided that the pedal car would best suit a council fleet vehicle scenario.

The final concept is half bike, half car: the layout of a passenger sports car with the driveline, brakes and suspension from a bicycle. This amalgamation will be significantly more sustainable than any passenger car on the road while maintaining passenger comfort and practicality.

After an analysis of current council fleet vehicles, it was evident that most usage scenarios only involved one person; and when passengers were recorded, most often there would be a maximum of two occupants. Given that the most common vehicle was a Toyota Corolla which is designed for 5 people, evidently council vehicles could be significantly downsized.

Initial research for the project included: Statistics Analysis, Secondary Research, Competitor Analysis, Technical Analysis, CAD Modelling and a Mock Chassis with Position analysis.

Mock chassis analysis was the most revealing research method so far. Helped to define definite adjustment envelopes for crank reach and height, steering lever reach and headrest height (will require depth adjustment).

The chassis of the pedal car will be constructed from aluminium tubes and lugs of a yet to be determined material. However the prototype will use 3D printed PETG lugs for prototyping flexibility and cost effectiveness. 

This concept is lightweight, allows for changeable geometry during prototyping, as well as a fast assembly time for production.

The pedal car has independent, double wishbone front suspension geometry, hydraulic mountain bike brake calipers and discs and rear MTB shocks used as coilovers. Rose-joints are used for their adjustability and fine articulation.

For the wheels and tyres, I chose to use 20" BMX rims, 2.4" wide BMX tyres and front MTB disc hubs. This combination is strong, lightweight, heavily customizable and has a comparable sidewall height to road cars.

Single pivoting crank mount covers the required reach and height adjustment for both 5th and 95th percentiles, and negates the need for a chain tensioner simplifying the driveline significantly.

A gear multiplier sprocket is used to reach 60kph pedalling at a cadence of 100rpm.

Ladder bar, solid axle rear suspension is used for its simplicity and compatibility with a chain-drive mechanism.

The cogs of a freewheel cassette are selected through a bicycle derailleur. 

Is controlled via two levers attached via rods to a rack and dual pinions. The levers fold to a horizontal position for a more comfortable ingress/egress and can be locked into place in the desired position for steering.

Braking is controlled through two MTB hydraulic levers: one for the front brakes and one for the rear.

*Steering wheel was considered, but found through mock chassis analysis to be unpractical in a pedal car due to the leg movement.

Given the 1 semester time-frame, I am pleased with my progress. There is still a fair amount of problem solving required before the chassis is ready to build, but I am happy with the direction of the overall concept.

Some of the feedback included that I should better define the how the pedal car will be used, outline the electric assist system and reconsider the driver position to better suit a council usage scenario.

My plan is to redesign the chassis to literally transform to the needs of the specific driver; just as the cranks, steering levers and neck-rest can be adjusted, so too will be the vehicle height.

Coming next semester will be a more targeted user research,  a design and CAD model of the body and a full chassis prototype.